BUH1215 STMicroelectronics, BUH1215 Datasheet - Page 4

• Manufacturer Part Number: BUH1215
• Description: High Voltage Fast-switching Npn Power Transistor
• Manufacturer: STMicroelectronics

BUH1215
4/7
Reverse Biased SOA
BASE DRIVE INFORMATION
In order to saturate the power switch and reduce
conduction losses, adequate direct base current
I
100
negative base current I
transistor to turn off (retrace phase).
Most of the dissipation, especially in the
deflection application, occurs at switch-off so it is
essential to determine the value of I
minimizes power losses, fall time t
consequently, T
defined to give total power losses, t
function of I
B1
has to be provided for the lowest gain h
o
C (line scan phase). On the other hand,
B1
at 64 KHz scanning frequencies for
j
. A new set of curves have been
B2
must be provided the
s
and t
B2
f
f
which
FE
and,
as a
at
choosing the optimum negative drive. The test
circuit is illustrated in figure 1.
The values of L and C are calculated from the
following equations:
Where I
flyback voltage, f= frequency of oscillation during
retrace.
1
2
L I
2 f
C
2
C
1
2
= operating collector current, V
L
1
C V
C
CEfly
2
CEfly
=